ESP32 WiFi scan: how to find and connect to networks

When WiFi won’t connect, scanning is your best “reality check.” It tells you:

• Is your SSID actually visible from where the ESP32 is?
• Is it strong enough to be stable?
• Are you accidentally targeting a 5GHz-only network name?

ESP32 WiFi scan sketch

#include <WiFi.h>

void setup() {
  Serial.begin(115200);
  delay(200);

  WiFi.mode(WIFI_STA);
  WiFi.disconnect(true); // ensure we start “clean”
  delay(200);

  Serial.println("Scanning...");
  int n = WiFi.scanNetworks();
  if (n <= 0) {
    Serial.println("No networks found.");
    return;
  }

  Serial.print("Found ");
  Serial.print(n);
  Serial.println(" networks:");

  for (int i = 0; i < n; i++) {
    Serial.print(i + 1);
    Serial.print(") ");
    Serial.print(WiFi.SSID(i));
    Serial.print("  RSSI: ");
    Serial.print(WiFi.RSSI(i));
    Serial.print(" dBm  ");
    Serial.print("  Encryption: ");
    Serial.println((int)WiFi.encryptionType(i));
    delay(10);
  }
}

void loop() {}

How to use the scan results

1. Find your SSID in the list and check RSSI.
2. If RSSI is worse than about -70 dBm, move the ESP32 closer before troubleshooting code.
3. If you don’t see your SSID at all, check your router (2.4GHz enabled, SSID broadcast enabled) or try a different location.

Connecting after a scan

Once you know the SSID is visible and strong, use the minimal connection sketch from the WiFi connect FAQ and build from there.

Related: Connect ESP32 to WiFi · Weak signal / connection failed · Disconnects / stays disconnected